Web cutoff device



Ammo WWW P. J. CHRISTMAN 9 9 WEB CUTOFF DEVICE Filed Nov. 12, 1946 m m H MN T*TT?*I A5 2 Sheets-Sheet l 9 P. J. cHmsTMAN 2,478,24U

WEB CUTOFF DEVICE Filed Nov. 12, 1946 2 Sheets-Sheet 2 INVENTOR.

Patented Aug.- 9, 1949 WEB CUTOFF DEVICE Peter J. Chrlstman,

Green Bay, Wis., Paper Converting Machine assignor to Co. Inc., Green Bay,

Wis., a corporation of Wisconsin Application November 12, 1946, Serial No. 709,189

9 Claims.

This invention relates to improvements in web cutofi devices, and is particularly adapted for use in connection with apparatus for handling webs of material such as paper wherein the webs must be severed at regular intervals.

It is a general object of the present invention to provide a web cutofl' device which is capable of operating efllciently at high speed so as to'be adapted for use in connection with modern high speed production machinery.

A further object of the invention is to provide a web cutoff device, of the type having cooperating cutting rollers provided with co-acting knives, wherein the knives are disposed in a novel manner with respect to one another so as to insure the proper amount of pressure to cause an emcient shearing of a web passing between the two rolls.

A more specific object of the invention is to provide a device as above described wherein the knife in one of the rolls extends in a plane which is at an acute angle with respect to the axis of the roll, and wherein the cutting edge of the knife is inclined with respect to the surface of the roll.

A more specific object of the invention is to provide a device as-above described wherein the angled and inclined knife of one roll co-acts with a straight knife set into a longitudinal groove in the periphery of the other roll, the high part of the inclined cutting edge entering into shearing relationship with the straight knife on the other roll in advance of the bite of the two rolls, and said high part being accommodated in the groove as rotation progresses and as the point of shearing contact progresses toward the low end of the inclined cutting edge.

A still further object of the invention is to provide a web cutoff device as above described having means for readily varying the knife adjustment to obtain a proper cutting action.

Other objects of the invention are to provide a web cutoff device which is relatively simple and inexpensive to manufacture, which is eflicient in operation, and which is otherwise well adapted for the purposes described.

With the above and other objects in view, the invention consists of the improved web cutoff device, and all its parts and combinations, as set forth in the claims, and all equivalents thereof.

In the accompanying drawing, illustrating one complete embodiment of the preferred form of the invention, in which the same reference numerals designate the same parts in all of the views,

Fig. i is a fragmentary vertical sectional view 2 through a cutoff device showing the cutting rolls principally in front elevation with parts broken away and shown in section;

lFIig. 2 is a cross sectional view through the two re s;

Fig. 3 is an enlarged, fragmentary, transverse sectional view showing the cutting action of Fig. 2 more clearly Fig. 4 is a top view of the lower roller of Fig. 2 looking down on the cutting knife;

Figs. 5, 6 and 7 are schematic perspective views illustrating the shearing action. the dot and dash lines indicating the cutting edge of the knife of the cooperating roll; and

Figs. 8, 9 and 10 are enlarged fragmentary cross sectional views taken along the lines 8-8, 9-9, and I ll-|0 of Figs. 5, 6 and 7 respectively.

Referring more particularly to the drawing,

the numerals I 0 and II designate frame portions in which trunnions l2 of a cutting roll I3, and trunnions I4 of a cutting roll ii are suitably journalled. Keyed to the projecting end of one of the trunnions I2 is a gear i6, and keyed to the projecting end of a corresponding trunnion I4 is a gear I'I. Either one of the gears i6 or ll may be driven from an outside source. When so driven, it is clear that, in the illustrated embodiment of the invention, the roll l5 will make two revolutions for every single revolution oi the roll i3. This particular relationship, however, may be varied to suit particular requirements.

The roll I3 is provided with oppositely disposed knives l8 which are preferably arranged in axially extending peripheral grooves IS, the grooves being 'open in advance of the knives. Each knife may be removably held in position by an elongated holding strip 20 having screws 2i extending therethrough and into the roll. Each knife is so arranged that its cutting edge 22 is close to the periphery of the roll with the edge extending straight and parallel with the axis of the roll i3.

The other cutting roll l5 has its periphery formed with a groove 23 which extends in a plane at an angle with respect to the axis of the roll, as is clear from Fig. 4. Removably insertable in said groove is a holder 24, which is preferably U-shaped in cross section, for a knife 25.

Screws 28 which are threaded into openings .21, are adapted to engage opposite sides of the holder to releasably clamp the holder in position and to clamp the knife within the holder. In order to facilitate access to the ends of the screws 26 the periphery of the roll may .be notched out on opposite sides of the knife, as at 28.

having their heads On the opposite side of the roll it from the knife recess 23 there is a groove 29. Screws 30 positioned in the groove 29 are threaded radially through the roll and have their inner ends engageable with the holder 24. as is clear from Figs. 1 and 2.

The cutting edge 8| of the knife 25 is inclined with respect to the surface of the roll, as is clear the angle of the knife clear that the cuttin from Fig. 1, and due to groove 23, it is, therefore,

,edge 3|, in addition to being inclined, also extends in a plane which forms the acute angle a of Fig. 4 with the axis of the roll l5. Thus, the angle a plus the inclination of the cutting edge 3i shown in Fig. 1 produces a double angle for the cutting edge.

By loosening the screws 26, and by manipulating the screws 30, as required, the knife holder and knife may be adjusted in the groove 23 to a proper position for most eflicient cutting action.

During use of the web cutting device, with the rolls rotating in the direction indicated by the arrows in Figs. 5, 6 and 7, and with the web of paper or other material to be cut traveling in the direction indicated, the high part of the inclined edge 3| of the knife 25 willfirst enter one of the grooves iii, in advance of the bite of the rolls, to co-act with the cutting edge 22 of one of the straight knives I8 as is illustrated schematically in Figs. 5 and 8. Shearing is performed by the back part of the cutting edge 3| as is clear from Fig. 3. In Figs. 5, 6 and '7 the dot and dash lines represent the knives l8 of the roll l3. Due to the angle a, shown in Fig. 4, and to the inclination of the cutting edge, there will be a shear cut with shearing contact taking place progressively along the length of the inclined cutting edge 3| from its high end as illustrated in Figs. 5 and 8, toward a point intermediate the length of the knives as is illustrated in Figs. 6 and 9, and finally to the low end, as is illustrated in Figs. '7 and 10. The shearing action is substantially completed when the cutting edge 22 is at the point of closest contiguity with respect to the roll l5 or at the bite of the rolls, as in Fig. 10. The angle a of the knife 25 must be such as to cause the shearing action to be completed during movement of the rolls from the position of Fig. 8 to the position of Fig. 10. As the shearing action progresses from its starting point of Figs. 5 and 8, the higher parts of the inclined cutting edge 3| slide past the cutting edge 22 and are accommodated within the groove 19. The width of the groove l9 must, therefore, be suilicient to accommodate the angled knife 25 when the parts are in the position of Fig. at the end of the shearing stroke. The adjustment screws 28 and 30 make it relatively easy to maintain the cutting edges in proper adjustment to accomplish the above-described action and make it possible to make minor adjustments in the inclination of the edge 3|. In order to obtain'eflicient results, there must be no play in the rolls or in the gearing therefor. The screws 26 make it possible to readily remove the knives 25, when required, for sharpening or replacement.

While the form of invention illustrated in the drawing illustrates the roll l3 as a two-time roll with two knives l8, it is obvious that the size of the roll may be increased to provide for more than two knives, or the diameter of the roll I3 may be decreased to the same dimension as the roll l5 to provide for the use of only one knife I8.

Various other changes and modifications may be made without departing from the spirit of the invention, and all of such changes are contemplated as may come within the scope of the claims.

I claim:

1. A web cutoff device comprising a first rotatably mounted roll having a knife adjacent its periphery provided with a cutting edge which extends straight and axially of the roll, a second roll rotatable with said first roll and positioned to co-act therewith, said second roll having a knife which extends generally longitudinally of the roll but in a plane which is at an acute angle with respect to the axes of said rolls, the cutting edge of said angled knife being inclined with respect to the surface of the roll, said angled knife being positioned so as to co-act with the knife of the first roll in producing a shearing action during rotation of the rolls.

2. A web cutoff device comprising a first rotatably mounted roll having a knife adjacent its periphery provided with a cutting edge which extends straight and axially of the roll, a second roll rotatable with said first roll and positioned to co-act therewith, said second roll having a knife which extends generally longitudinally of the roll but in a plane which is at an acute angle with respect to the axes of said rolls, the cutting edge of said angled knife being inclined with respect to the surface of the roll, said angled knife being positioned so that the high end of its inchned edge co-acts with the cutting edge of the straight knife of the first roll in advance of the bite of the two rolls.

3. A web cutoff device comprising a first rotatably mounted roll having a knife adjacent its periphery provided with a cutting edge which extends straight and axially of the roll, a second roll rotatable with said first roll and positioned to co-act therewith, said second roll having a knife which extends generally longitudinally of the roll but in a plane whzch is at an acute angle with respect to the axes of said rolls, the cutting edge of said angled knife being inclined with respect to the surface of the roll, said angled knife being positioned so that the high end of its inclined edge co-acts with the cutting edge of the straight knife of the first roll in advance of the bite of the two rolls and the angle of the plane of the knife of said second roll being such that shearing action is substantially completed when the low end of the inclined edge is at the bite of the rolls.

4. A web cutoff device comprising a first rotatably mounted roll having a knife adjacent its periphery provided with a cutting edge which ex tends generally longitudinally of the roll, a second roll rotatable with said first roll and positioned to co-act therewith, said second roll having a knife which extends generally longitudinally of the roll but in a plane which is at an acute angle with respect to the cutting edge of the knife of the first roll when said knives meet during rotation of the rolls, the cutting edge of said angled knife being inclined with respect to the surface of the roll and said angled knife being positioned so as to co-act with the knife of the first roll in producing a shearing action during rotation of the rolls.

5. A web cutoff device comprising a first rotatably mounted roll having a knife adjacent its periphery provided with a cutting edge which extends straight and axially of the roll. a second roll geared to said first roll and positioned to co-act therewith, said second roll having a knife which extends generally longitudinally of the roll amaeeo but in a plane which is at an acute angle with respect to the axes of said rolls, the cutting edge of said angled knife being inclined with respect to the surface of the roll, said angled knife being the roll but in a plane which is at an acute angle with respect to the axes of said rolls, the'cutting edge of said angled knife being inclined with respect to the surface of the roll, said angled knife being positioned so that the high end of its inclined edge cc-acts with the cutting edge of the straight knife of the first roll in advance of the bite of the two rolls and the angle of the plane of the knife of said second roll being such that shearing action is substantially completed when the low end of the inclined edge is at the bite of the rolls, there being a longitudinal space in advance of the cutting edge of the knife of the first roll for accommodating the knife of said second roll.

7. A web cutoff device comprising a first rotatably mounted roll having a knife adjacent its periphery provided with a to co-act therewith, said second roll having a knife which extends generally longitudinally of the roll but in a plane which is at an acute angle with respect to the axes of said rolls, the cutting edge of said angled knife being inclined with respect to the surface of the roll, said angled knife being positioned so that the high end of its inclined edge co-acts with the cutting edge of the 6 shearing action is substantially completed ,when the low end of the inclined edge is at the hiteof the rolls, said first roll having a longitudinal sToove in advance of the cutting edge 'of'its'knife for accommodating the knife of said second roll. 3. A web cutoff device comprising a first rotatably mounted roll having a knife adjacent its I periphery'provided with extends straight and axially of the roll, a second me of .the roll but in a plane a cutting edge 1 which roll rotatable with said first roll and positioned to co-act therewith and having a groove in its periphery which extends generally longitudinally of which iszat an acute angle with respect to the axes of said rolls, a' knife holder removably positioned in said groove,'a

knife removably positioned in said holder, and

means for removably maintaining said holder and knife in position in the groove of said roll. 9. A web cutofidevice comprising aiirst rotatably mounted roll periphery provided with a cutting edge which ex-' tends straight and axially of the roll, .a second roll rotatable with said first roll and positioned .to co-act therewith and having a groove in its periphery which extends generally longitudinally of the roll but in a plane which is at an acute angle with respect to the axes of said rolls, a knife holder removably positioned in said groove, a knife removably positioned in said holder, r-adially extending adjustment screws in said roll engageable with said holder for adjusting the radial position of the knife, and atleast one transversely extending adjustment screw-for re.- leasably maintaining the holder and knife in a selected position of adjustment.

PETER J. CHRISTMAN.

REFERENCES CITED The following references are of record in the this patent:

UNITED sums PATENTS Date having a knife adjacent its- 

